Pull-request

Comments

Bug reference:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1169376
XPS13 backlight stopped working after update 3.8.0-18.28
[IMPACT]
My recent sauce patch for LP: #1162026 (Raring 9742db3) applied a quirk to
fix the backlight controls on two variants of the Dell XPS13, but it turns
out that the quirk is only appropriate for the original 768p model (there
was some misunderstanding about which models needed it).
The new Dell XPS13 "FHD" 1080p model is actually adversely affected by the
quirk, yielding dark screen on boot and no backlight controls. This patch
removes the 1080p model from the dmi quirk table, restoring its backlight
behavior to normal functionality.
[TESTCASE]
The bug reporter in LP: #1169376 has confirmed that a test kernel with the
patch applied fixes it for his 1080p model. I have confirmed that the
original quirk patch still works on my 768p model.
[Regression Potential]
Low regression potential: the change only affects the Dell XPS 13 "FHD" 1080p
model, returning its i915 backlight controls to the standard mainline
(pre 3.8.0-18.28) behavior.
Thanks,
-Kamal
-------- >8 ----------------------------------------------------
The following changes since commit 10e251b7b13b2c727d58a7d3ed4451667366ad12:
UBUNTU: SAUCE: (no-up) ACPI: Disable Windows 8 compatibility for some Lenovo ThinkPads (2013-04-19 07:29:30 -0700)
are available in the git repository at:
git://kernel.ubuntu.com/kamal/ubuntu-raring.git lp1169376-xps13-fhd
for you to fetch changes up to ba44c190aafad79f11e6b5477de26f81b8fdb3ac:
UBUNTU: SAUCE: (no-up) drm/i915: quirk no PCH_PWM_ENABLE only Dell XPS13 SandyBridge (2013-04-19 08:52:52 -0700)
----------------------------------------------------------------
Kamal Mostafa (1):
UBUNTU: SAUCE: (no-up) drm/i915: quirk no PCH_PWM_ENABLE only Dell XPS13 SandyBridge
drivers/gpu/drm/i915/intel_display.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

On Fri, 2013-04-19 at 10:49 -0600, Tim Gardner wrote:
> > Kamal Mostafa (1): UBUNTU: SAUCE: (no-up) drm/i915: quirk no> > PCH_PWM_ENABLE only Dell XPS13 SandyBridge> > > > I would like the commit subject to be grammatical. This one just makes> my head hurt.> >
Wow reading it again... what a mess, sorry!
I tried to encode the concept: "Unapply the 'do not enable PCH_PWM'
quirk from the model that doesn't need it."
Thanks for fixing it for me, Tim.
-Kamal